Add $PREFIX to pkg command
Add "is pkg used" check
Simplify return code handling
Minor improvements
Rename 460.chkpkgsum to 460.pkg-checksum for uniformity
Fix bunch of typo and copy/paste mistakes. Remove redundant comments
Merge remote-tracking branch 'origin/master' into periodic
Merge pull request #428 from aklv/periodic

Improvements to periodic scripts.